So i made friends with someone who is also majoring in psychology and we got to talking about ketch.
LawfulRhi is friggin amazing by the way

Arthur Ketch

I’d like to think that people are
not innately ‘evil’, but rather they are a product of their environment & the
people within it (Nature & Nurture). Those aren’t the only things that
impact who a person becomes, but I think it’s safe to say at least SOME aspects
of his personality are resultant of this. Ketch comes off as someone who is
excellent at smothering his emotions and regrets. We feel that this is possibly
resultant of long term conditioning or the brain washing treatment that Mary
was subjected to at the end of the season.

Perhaps it is a combination of both
and there are obviously a billion other possible reasons/speculations. I am
unsure if this is accurate, but if my memory serves me well, Ketch joined the
organization to have access to superior weaponry. Another question to keep in
mind is whether or not the organization itself is what made Ketch think in the
manner that he does. Did something happen in his past that made him this
so-called cold blooded killer? Did he lose his family to monsters? What other
situations could he have been subjected to that had a lasting impact on his
personality?

We know he is ‘wired’ to prioritize
the organization over all things. The life of a hunter can be described as all consuming,
no matter who they answer to (or don’t). The BMOL have very strict rules. One
step out of line and you’re most likely dead before you can blink. That may be
why he applauded Mary at first for wanting to hunt and have a family (he told
her “good for you” and seemed to mean it), which could possibly mean
that he was impressed by the bravery it takes to do something like that, which might
mean he struggled with that choice in the past. By his actions, we can infer
that he has some sort of a soft spot and IS capable of (some form) of love. I
think the BMOL, Angels, and Demons alike would all classify his relationship
with Mary Winchester as a ‘weakness’, something or someone who is important
enough to make the person in question hesitate. In the supernatural world,
compassion, love, and emotional ties all have the potential to get you killed.
All a monster needs is a split second of lost concentration and that could be
game over for the hunter.

After he slept with Mary and she
informed him that it was a “one time thing”, he was noticeably upset
(Props to DHJ for the amount of emotion he conveyed with his eyes btw.) There
was a scene where Mary and Ketch were in the room with the TVs that displayed
all the main American Hunters’ Information. I remember that he begged/asked her
to let the extermination operation slide or something to that extent. Had it
been anyone else, I feel like he wouldn’t have hesitated to do what he did to
Mick. I need to rewatch these scenes, but from what I remember he has a moment
where he doesn’t speak and you can tell he’s really thinking about his options.
Then his face “hardens” and you KNOW what his decision is before he
even opens his mouth.

Is it possible that part of the
reason her to let it go was not only because he did care for her as she was,
but he was also aware of the fact that she was a gifted enough hunter that they
would rather program her than kill her? If that is true then he was not only
try to spare her physically, but he was also trying to spare her the
conditioning that he knew they would do. We then have to ask ourselves how he
would know such a thing. Could this mean he was on the recovering end of such a
process? When Mary was brainwashed he kept speaking like it was from
experience, “It will be over soon, I promise!” And there was quiet
horror when he saw how much she had changed after it was done (in their
personal conversations in the car), like he just now saw what he had allowed
himself to become. There is a lot more
speculation to be done in all honestly. His character was a major source of
interest from day one for both of us. We are both psychology majors and this just kinda happened xD.